乳清蛋白组分在脱脂乳和乳清体系中热变性率的比较研究  

Comparison of thermal denaturation rate of whey protein components in skim milk and whey systems

作　　者：麻志宁 王媛媛 李红娟[1] 李洪波[1] 于景华[1] MA Zhining;WANG Yuanyuan;LI Hongjuan;LI Hongbo;YU Jinghua(Tianjin University of Science and Technology,College of Food Engineering and Biotechnolo gy,Tianjin 300457,China;Plum flower biotechnology group Co.Ltd.,Langfang 065000,China)

机构地区：[1]天津科技大学食品工程与生物技术学院,天津300457 [2]梅花生物科技集团股份有限公司,河北廊坊065000

出　　处：《中国乳品工业》2019年第12期4-8,共5页China Dairy Industry

基　　金：国家自然科学基金（31671876）;青年科学基金项目（31601496）;新型饮用型酸奶风味控制与改善关键技术研究（17227111D）

摘　　要：脱脂乳粉生产过程的预杀菌工艺对乳清蛋白变性有很大影响,乳清蛋白的变性程度主要取决于温度和时间的变化。本文对脱脂乳体系和乳清体系进行55~95℃,1~30 min加热处理,通过反相高效液相色谱(RP-HPLC)检测加热后样品中乳清蛋白主要组分并进行比较分析。结果表明:在脱脂乳体系与乳清体系中,牛血清白蛋白(BSA)变性趋势基本相同,温度达到65℃时变性显著,85~95℃几乎全部变性。α-乳白蛋白(α-La)的变性率在温度低于75℃时变性率差异较小,而在75~95℃的加热范围内变性率区别明显。β-乳球蛋白(β-Lg)在75~85℃加热范围内变性率有明显差异,3种乳清蛋白组分的热变性程度均显示出受热时间和温度的累积效应,最终趋向全部变性。与脱脂乳中蛋白热变性比较表明,酪蛋白对乳清蛋白中牛血清白蛋白的变性影响不大,而在65~95℃间对α-乳白蛋白、β-乳球蛋白的热变性有一定的促进作用。The denaturation of whey protein was greatly affected by the presterilizing process of skim milk powder. The denaturation degree of whey protein mainly depended on the change of temperature and time.The article analyzed the influence of casein to whey protein denaturation. Two kind of samples, skim milk system and whey system, were both heated under 55~95 ℃, 1~30 min and detected by reversedphase high-performance liquid chromatography(RP-HPLC). The results showed that the denaturation trend of bovine serum albumin(BSA) was basically the same in skim milk system and whey system.When the temperature reaches 65 ℃, the denaturation is remarkable, and almost all of them are denatured at 85~95 ℃. The variation rate of α-lactalbumin(α-La) is small when the temperature is lower than 75 ℃,but the difference is obvious in the heating range of 75~95 ℃. and the denaturation rate of β-lactoglobulin in the range of 75~85 ℃ is obviously different. The thermal denaturation degree of the three components of whey protein showed the cumulative effect of heating time and temperature, and the denaturation degree was more affected by temperature than by time.Compared to the protein denaturation of skim milk showed that casein had no effect on bovine serum albumin, but it promoted heating denaturation of α-lactalbumin and β-lactoglobulin between 65~95 ℃.

关 键 词：乳清蛋白 热变性 牛血清白蛋白 Α-乳白蛋白 Β-乳球蛋白 

分 类 号：TS252.1[轻工技术与工程—农产品加工及贮藏工程]